Plenum Chamber Drain Grommets - Every A4 B6 owner is affected by this common fault

well done mate. this will be the start of a beautiful obsessive compulsive disorder, ending eventually in a desire to change your own timing belt :)

thanks pal- you seem to be quite competent yourself mate judging by your belt issue on your other earlier thread- so your a more capable man than me
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. the thing is i get so excited by all the mods i read on here that can be done to enhance my motor for relatively little expense, which i would love to do
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but then i get deflated with the realisation i am incapable of doing any of it myself!!
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Good news but some gunge do you get a lot of Guano where you live?Mines mainly due to the neighbours trees overhanging the drive so I have started using a windscreen cover in autumn to shield the intake grill and made some mesh covers for the big openings round the battery chamber which seem to suck the rubbish in

good idea mate- i suppose i could just stick mine in my garage instead.
 
just removed mine refitted everything, started car it ran for 30 seconds, then cut out now wont start and fuel gauge says empty.....?????? i know theres at least £15 lol even if that is only about 2 litres at todays fuel prices. No faults in vcds so really stumped :(
 
that's a weird one. I can't work out how disconnecting the battery would tell the fuel gauge there's no juice there.
I'd be inclined to fill a jerry can and throw that in just to ease any paranoia that it's magically leaked away somewhere. I once spent an hour looking at my brother's car when it wouldn't start. he swore blind there was petrol in it but eventually I worked out there wasn't. Couldn't find a leak and the car didn't magically lose petrol afterwards so god knows how he was wrong.. but it happened.
 
Well today whilst turning out my drive i noticed the sound of splashing water. I remembered reading this thread. So popped the bonnet to find around 3-4 inches of water lying in the plenum chamber. Gave Audi a quick call to see if they sort it on the recall. I j
Have a 2004 a4 tdi quattro sport. They checked my chassis number and said it want one of the affected models. I told them obviously it was or I wouldnt have my battery skinny dipping in the plenum chamber. He wouldn't budge and offered to look at it for £90. Eh no!

I tried to get the battery out but couldn't find an allan key long enough. So jacked the car up stuck it on axel stands and removed the rear under tray. Looked up and spotted the 2 offending articles. Pulled them out with a set of long nosed pliers and subsequently soaked myself. Couldn't believe the amount of crap that was in there. I was going to clean them and put them back in but sod it I'l just keep an eye it and give it a regular flush out with water.

If you plan on removing them it took 5 mins with car up.

Thanks so much for this thread or it may have been costly
 
haha - yeah, just keep them out. I just touched mine and they went. Its a ****** lot of water! :)
 
Well today whilst turning out my drive i noticed the sound of splashing water. I remembered reading this thread. So popped the bonnet to find around 3-4 inches of water lying in the plenum chamber. Gave Audi a quick call to see if they sort it on the recall. I j
Have a 2004 a4 tdi quattro sport. They checked my chassis number and said it want one of the affected models. I told them obviously it was or I wouldnt have my battery skinny dipping in the plenum chamber. He wouldn't budge and offered to look at it for £90. Eh no!

I tried to get the battery out but couldn't find an allan key long enough. So jacked the car up stuck it on axel stands and removed the rear under tray. Looked up and spotted the 2 offending articles. Pulled them out with a set of long nosed pliers and subsequently soaked myself. Couldn't believe the amount of crap that was in there. I was going to clean them and put them back in but sod it I'l just keep an eye it and give it a regular flush out with water.

If you plan on removing them it took 5 mins with car up.

Thanks so much for this thread or it may have been costly

I totally agree, i was very happy i read this thread too as it certainly helped me. At least you didn't get a mouthful of dirty rainwater mate...(i was stupid enough to try a siphon,lol.) i think next time i will try getting mine on a ramp of some sort too and clean them from underneath as i found it a pain taking the battery off etc, mind you i managed to find a long allan key set from halfords which did the job for me.
 
I had a set of hex sockets and an extension but as usual there wasn't enough room to get the shoulder of the socket in to get the ****** bolt out. Audi have a very nasty habit of making everything ****** difficult lol

Another thing I did note was when I disconnected the battery i seemed to have lost 100miles worth of diesel lol. I think it's because it's reset the onboard computer. So my average mpg went from 45 ( its a quattro) to 32 lol
 
That How to guide at the top of this thread no longer works!
Don't just assume that if the area is dry you don't have a problem.
Heavy rain will cause water to drain into the cabin under the carpets (or worse) but will eventually drain through the grommets leaving no telltale signs. A nasty damp smell when you first get in the car is the first obvious sign you have a problem.
Just take out the battery (6mm allen key needed and 10mm spanner) and remove the grommets, don't waste your time going to Audi.
 
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Just done mine after a limp mode problem in heavy rain. There was a small amount of water still in the chamber the next day so on Quattrojames advice I had a look at them. I didn't refit them.

Thanks for the thread guys.
 
After 2 years with no sign of water noticed about an inch today so my luck had run out! Not wanting to remove the battery released the clamp which allowed this to be lifted enough to see the grommet at the back of the chamber which easily pushed out.Could not get at the other one but this will do as I see no point in putting anything back in the hole and I have to leave the car on the drive under trees which drop litter all year.After going through this with a B5 I assumed it was sorted but should have checked before
 
After 2 years with no sign of water noticed about an inch today so my luck had run out! Not wanting to remove the battery released the clamp which allowed this to be lifted enough to see the grommet at the back of the chamber which easily pushed out.Could not get at the other one but this will do as I see no point in putting anything back in the hole and I have to leave the car on the drive under trees which drop litter all year.After going through this with a B5 I assumed it was sorted but should have checked before

The other one can be 'got at' by removing the battery and going in from that side. However, there is (or at least there was on mine) a brake pipe that goes through the grommet on that one which makes it a bit more awkward to remove. I just cut mine with a pair of side cutters (the grommet that is, not the pipe!!!!!!).
 
The other one can be 'got at' by removing the battery and going in from that side. However, there is (or at least there was on mine) a brake pipe that goes through the grommet on that one which makes it a bit more awkward to remove. I just cut mine with a pair of side cutters (the grommet that is, not the pipe!!!!!!).
Thats useful to know if I change the battery I have a look but hoping the one now open will cope and will check more often .Thanks Mike
 
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Hi guys, i know this is an old post etc but i think this issue could have been the cause for my car not starting up yesterday morning after a night in heavy rain. I had a look around my battery and servo area and cant really see any water but cant see the grommits im supposed to remove either. I had a feel around but without success. Given that the 'How to fix this problem' link posted above does not work, could someone please point me to the right direction?

Incidentaly when i spoke to Audi Sheffield about this they said 'the only outstanding campaign for your vehicle is to check the coil packs'. ' There is nothing in relation to the plenum chamber. There may be a reasoning behind the non starting issue after rain - This can be checked on the day if required - There will be a diagnosis charge of £56.99 inc vat. If you have the repair work carried out then the diagnosis cost will be re-imbursed'.
Needless to say I need to do this myself!
 
The gromets are under the battery iirc.

Maybe someone would be good enough to do a mini 'how to' guide when they do this as the original link is fubar.
 
hi guys

dont know if this will help but i saved this guide below which definately helped me.
the grommet is under the battery and was easy once the battery is out, the servo one is then much easier to locate.


- under the bonnet remove the plastic cover across the top of the battery byremoving the rubber strip that runs the full width of the car. Just pulls off.
- Disconnect the negative lead on the battery then the positive which has twonuts to undo.
- The battery is secure on the front side of the battery at the base with aallen key head. A long allen key is required for this.
- Lift the battery out
- Two nuts secure the battery support bracket. Below this is the first grommet(cam shaped rubber thing) which just pulls out.
- From memory you can then reach across to the drivers side below the brakeservo (big round black thing) to get to the other grommet. There will probablybe a cable/ wire running through the grommet itself. I just pushed the grommetthrough the hole and left it connected to the cable but you could cut thegrommet free.

Reverse order to replace and always replace positive first then negativesecond.

I think you have a couple of hours of the battery being disconnected before youwill need the radio code.
To make the key work again, put it into the ignition, turn to position 2 andpress unlock and lock together.
The traction control light will be on after replacing the battery and startingthe engine. This will go out when you start driving.

 
After 2 years with no sign of water noticed about an inch today so my luck had run out! Not wanting to remove the battery released the clamp which allowed this to be lifted enough to see the grommet at the back of the chamber which easily pushed out.Could not get at the other one but this will do as I see no point in putting anything back in the hole and I have to leave the car on the drive under trees which drop litter all year.After going through this with a B5 I assumed it was sorted but should have checked before
So glad that I did this just in time some places here on the s coast have had over 2 " of rain this morning.Just checked the chamber and saw no sign of standing water so content not to try and remove the other grommet yet
 
Looks like i have to do this on 2 cars... my sons has intermitant servo problem with water being present in the plenum and i've just been out to check my Avant and that has water in there too dispite having been stood in the garage for the last 6 months, so if i think on i'll try and take a few picks and do a write up ,,, are you all agreed that the best way is to remove the battery or to move the expansion tank and get at them from underneath ??? i'm going with battery out unless otherwise informed as then i can give it a good clean in there... just hoping there's no long lasting damage to my lads servo.... he aint havin mine.. ;)
 
Well i got up this morning and there's a puddle of water in the passenger footwell... i knew it was blocked but didn't realise it was this bad as the cars only been back on the raod for a week... so i went out at dinnertime as i'm in work and managed to loosen that very large grommet thats pictured in an earlier post without having to remove anything and got around 2 or 3 litres of water to drain out.. i'll be doing a proper job tomorrow but my question is where does the water enter the cabin ?? it wasn't so full of water as to be flowing over the polen filter so where does it get in ?? need to get the vax out now too and dry the ****** carpet out
 
Does anyone have any pics of the location of the grommets as the link on the first post is no longer working. I am currently working around the plenum chamber area on another problem and while it was all apart was going to look at this too. Many Thanks
 
Ok apologies I have just found on an earlier post it has already been said. Will look up under VW.

Thanks,
 
done mine today, water was up about an inch over the bottom of the battery, the original link on how to repair it has now changed to this Interior leaking | veedoubleu dot com the only difference is the battery holder on the a4 is in the front the passat looks easier to take out. My car is a 2004 by the way
 
Does issue affect the battery as i have noticed this build of water as a result of my battery going dead and having to jump start it and trying to replace the battery.

On the subject of changing the battery does anyone have an idiots guide on how to do this and i mean idiot step by step LOL

Thanks
 
The housing which holds my ECU(A4 B6 TDI) is flooded resulting in the 3 relays in there being submerged in water.
Does this issue with the grommets in the plenum effect this area also?
 
hI yer all

Allan key to remove the poxy bolt Audi puts in to hold the battery in

Step 1 find a decent tool factor when you enter the shop they should have brands like Facom, Britool, Wera, Gedore, Matarbo, Beta tools and Bosch but the blue range (professional range) you can get the green range anywhere (home uses)

Step 2 ask the person behind the counter if they do Gedore if they do ask them for to order product No.42T gedore code 6353910 I brought one of these makes the job easy it is 6mm T handle allen key 270mm long but Gedore is not the cheapest brand out there it a tool that is guaranteed for life and cost around £11 but you pay for what you get

Failing that and getting the run around from a draper tool factor as they are trying to source one off ebay, I'am sure other tool manufactures do this but I couldn't find any out there over 200mm long apart from Gedore and before any ones moans at me you buy a top quality tool once in your life and I've lent this tool to my mate at Halfords in Bridgwater when he needs to do audi A4

Gedore UK
Marton Street
Skipton

BD23 1TF
Tel: 01756 706700

hope this helps
 
Bought an A4 today, 1.9tdi AWX, one owner from new..

Was driving it this afternoon after a downpour and heard water slushing around in the bulkhead.

When i stopped raining, i stripped it down and removed the bungs..

The job was a little easier than when i did it on a Passat, as there is a little more room to remove the battery..

The clamp thing is a bit fiddly but now i know where it is, it will be easier if i have to do it again.
 
it would seam that my b6 has sufferd from this water issue. as its not got the original engine ecu that it left the factory with. iam going to check the other gromets tomorow.
 
Bringing this thread back to life. My A4 had NOT had the bungs removed and so I found my drivers side front and rear footwells quite 'moist'
Got rid of the ****** things once and for all, although the one under the servo is bit of a **** due to lack of access and the fact a brake line actually goes through the rubber bung itself, you have to cut it away.

Glad I did it, just got to get the car dry now!